how can I add already imported pictures to new album while importing new pictures

I exported all my picture from my Aperture-folders onto a harddisk. The result is that I have that same folder structure on my harddisk, but quite some pictures are exported to more than 1 folder. So the same pictures exists multiple times in different locations on my harddisk. That's ok so far.

Now I want to import those pictures into Photos, into new albums. Photos will give me an overview of the to be imported pictures, and give the choice 'Add all new pictures'. Photos will now import all pictures into it's big database and display the newly imported pictures as 'Recently added'. Now I select the new pictures and place them into my chosen photos album.

That's fine so far.

However: if Photos sees that I already have imported some pictures it will show them in the beginning of the import-preview. That's ok. I can now choose to either import only the new pictures or select all pictures, add the already existing pictures manually, and then import all pictures. The problem is that doing this I will create duplicates of already imported pictures.

That's not what I want.

What I do want is the following: Hey, Photos. See these pictures you are telling me you already imported them? Make a list of these somewhere where I can acces this list so that I can add those already imported pictures to the album of my choice. And after I have done that I will import all new pictures and place those in the same album.

What I do not want to do is checking the Photos database for those already imported pictures to add them manually to the new album. I am talking about a few thousand pictures I would have to do this for, that is not a task I am right now willing to perform!

Does anyone have an idea how I can avoid this?